/*
 *  linux/arch/arm/mm/pgd.c
 *
 *  Copyright (C) 1998-2005 Russell King
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#include <linux/mm.h>

#include <asm/pgalloc.h>
#include <asm/page.h>
#include <asm/tlbflush.h>
#include <asm/cacheflush.h>

#include "mm.h"

#define FIRST_KERNEL_PGD_NR	(FIRST_USER_PGD_NR + USER_PTRS_PER_PGD)

#include <linux/bootmem.h>
/*
 * need to get a 16k page for level 1
 */
pgd_t *get_pgd_slow(struct mm_struct *mm)
{
	pgd_t *new_pgd, *init_pgd;
	pmd_t *new_pmd, *init_pmd;
	pte_t *new_pte, *init_pte;

	// static int addr = 0xDA000000;
	// new_pgd = (pgd_t *)addr;
	// addr += (16 * 1024);

	new_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL, 2);
	printf("this is %s(): %d	new_pgd = 0x%x\r\n", __func__, __LINE__, new_pgd);
	if (!new_pgd)
		goto no_pgd;

	// memset(new_pgd, 0, FIRST_KERNEL_PGD_NR * sizeof(pgd_t));
	memset(new_pgd, 0, 16 * 1024);

	/*
	 * Copy over the kernel and IO PGD entries
	 */
	init_pgd = pgd_offset_k(0);
	// memcpy(new_pgd + FIRST_KERNEL_PGD_NR, init_pgd + FIRST_KERNEL_PGD_NR,
	// 	       (PTRS_PER_PGD - FIRST_KERNEL_PGD_NR) * sizeof(pgd_t));
	memcpy(new_pgd, init_pgd, 16 * 1024);

	// clean_dcache_area(new_pgd, PTRS_PER_PGD * sizeof(pgd_t));
	clean_dcache_area(new_pgd, 16 * 1024);

	// if (!vectors_high()) {
	// 	/*
	// 	 * On ARM, first page must always be allocated since it
	// 	 * contains the machine vectors.
	// 	 */
	// 	new_pmd = pmd_alloc(mm, new_pgd, 0);
	// 	if (!new_pmd)
	// 		goto no_pmd;

	// 	new_pte = pte_alloc_map(mm, new_pmd, 0);
	// 	if (!new_pte)
	// 		goto no_pte;

	// 	init_pmd = pmd_offset(init_pgd, 0);
	// 	init_pte = pte_offset_map_nested(init_pmd, 0);
	// 	set_pte_ext(new_pte, *init_pte, 0);
	// 	pte_unmap_nested(init_pte);
	// 	pte_unmap(new_pte);
	// }

	return new_pgd;

no_pte:
	// pmd_free(mm, new_pmd);
no_pmd:
	// free_pages((unsigned long)new_pgd, 2);
no_pgd:
	return NULL;
}
